During a wellbore drilling operation, drilling fluid or drilling mud is often used to flush out drilling cuttings and debris from the wellbore. The liquid part of the drilling mud typically passes through the walls of the wellbore and gets absorbed by the surrounding formation. However, the solid parts generally do not penetrate into the formation. Thus, the solid parts of drilling mud form a layer of residue, called filter cake, on the walls of the wellbore. Thus, after a drilling operation, filter cake remains in the wellbore. Typically, a wellbore will be cased with cement during well completion. The cement is formed against the walls of the wellbore. However, filter cake, if left on the walls of the wellbore, acts as an unstable barrier between the cement and the wellbore, and prevents the cement from being robustly attached to the wellbore. This may introduce instability to the wellbore. Thus, after certain drilling operations, filter cake needs to be removed from the wellbore through a cleaning operation using a wellbore cleaning tool.
To remove filter cake, a wellbore cleaning tool is lowered downhole into the wellbore and sprays a pressurized cleaning fluid onto the walls of the wellbore. The pressurized cleaning fluid impacts the filter cake with high enough momentum to break up the filter cake and remove it from the walls. The filter cake is then flushed out. Typically, the cleaning fluid is ejected from the cleaning tool via a series of ejection points on the cleaning tool. However, conventional cleaning tools are standardized in size with fixed ejection points. Thus, when the cleaning tool is used in a wellbore having a larger diameter or irregular shape, the distance between the wellbore walls and the cleaning fluid ejection points increases, or varies. Thus, the momentum with which the cleaning fluid impacts the filter cake decreases. This may result in more cleaning fluid used, longer operation time, and overall lowered efficiency and increased cost.